Mutations

AVPR2 is a receptor protein that helps maintain water homeostasis in humans. The binding of AVPR2 to antidiuretic hormone in the kidney promotes water retention, helping to prevent dehydration and electrolyte imbalance.

The AVPR2 protein is encoded by the AVPR2 gene. The structure of the AVPR2 gene is shown below. In the diagram, rectangles represent exons and horizontal lines represent introns.

Which of the following AVPR2 gene mutations would most likely affect a person’s ability to properly maintain water homeostasis?

(Choice A)
a single base-pair substitution at Site 1 that changes one lysine-encoding codon (AAA) to another (AAG)
(Choice B)
a single base-pair insertion at Site 2 that shifts the reading frame for subsequent codons
(Choice C)
a single base-pair deletion at Site 3 that removes an “A-T” nucleotide pair from the gene sequence
(Choice D)
a single base-pair substitution at Site 4 that results in an early stop codon

AP®︎/College Biology

Course: AP®︎/College Biology > Unit 6

Problem